A groundbreaking study has unveiled new insights into the connection between type 2 diabetes, frequently linked to unhealthy diets, and pancreatic cancer, a disease responsible for the deaths of 28 individuals in the UK daily.
Each year, approximately 10,800 cases of pancreatic cancer are diagnosed across the UK, positioning it as the tenth most prevalent cancer in the nation.
Published in JAMA Network Open, the recent study conducted by researchers in South Korea explored the potential relationship between diabetes and the risk of developing pancreatic cysts, some of which have the potential to progress into pancreatic cancer.
The pancreas, a pear-shaped gland roughly the size of a hand, is located deep within the abdomen behind the stomach. It plays a crucial role in producing insulin, a hormone essential for transferring sugar from the bloodstream into cells, where it is converted into energy.
Pancreatic cysts, which are fluid-filled sacs in the pancreas, are often discovered incidentally during scans and tend to become more common with advancing age.
Although these cysts are typically benign, meaning they are not cancerous, there are instances where changes occur in the cells lining the pancreatic duct, potentially leading the cyst to develop into a malignant tumor.
Because of its location – and its relatively small size – doctors often can’t feel a pancreatic tumour during a routine physical exam, which is another reason the disease is so difficult to detect early.
The connection between type 2 diabetes and pancreatic cancer is well-established but complex, often described as a ‘chicken and egg’ scenario because both diseases affect the pancreas.
The pancreas is a pear-shaped gland, about the size of a hand, tucked deep behind the stomach
Doctors first started exploring the possibility of a link between diabetes and pancreatic cancer in the 1940s and 1950s.
Several reports had come out saying that patients with pancreatic cancer were more likely to also have diabetes than other people. This has been shown for type 2 diabetes as well as type 1 and young-onset diabetes.
Since then, many studies have shown a link between the two conditions. Overall, it seems that people with diabetes are around twice as likely to be diagnosed with pancreatic cancer than the general population.
Roughly one in ten pancreatic cancers are caused by being overweight or obese and obesity is the primary driver of type 2 diabetes, accounting for 80–85 per cent of the overall risk.
The latest study, conducted by researchers from Seoul National University College of Medicine and other South Korean institutions, tracked 3.85million adults based on insurance claims data, 8.6 per cent of whom had diabetes, for ten years and compared people based on glucose status.
People were grouped into the following categories: normal blood sugar, prediabetes, those who had diabetes for less than five years and those who had diabetes for more than five years.
The researchers tracked who developed pancreatic cysts over time to find out how much higher the risk is in one group compared to another over time.
The study found that the longer someone had diabetes, the higher their risk of developing pancreatic cysts.
At any time point, people with long-standing diabetes had 1.37 times the risk of developing a pancreatic cyst compared to those with normal glucose levels.
Those who had lived with diabetes for more than five years had a 37 per cent higher risk compared with those who had prediabetes, who had a six per cent higher risk.
This risk was particularly elevated in individuals aged younger than 60 years with diabetes, males with diabetes and current smokers with diabetes.
Previous research found that around one in five pancreatic cancers are caused by smoking.
Cigarettes, cigars, pipes and chewing tobacco all raise the risk.
However, the JAMA Network Open study found that only 0.8 per cent of the population developed cysts over 10 years.
Among those who developed cysts, 4.1 per cent later developed pancreatic cancer. But in the total population, only 0.7 per cent developed pancreatic cancer overall.
The study highlights that younger diabetic men might warrant more attention.
Previous studies have found that getting older is one of the biggest risk factors for pancreatic cancer.
Almost half of cases are diagnosed in over-75s – and it is rare in under-40s.
This is a common theme across many cancers. As Cancer Research UK explains: ‘Over time, the cells in our body become damaged. Cancer develops when damage in the same cell builds up.’
Despite this, pancreatic cancer incidence is rising more rapidly in younger age groups.
There is debate among researchers regarding whether this represents a true increase in cancer cases or increased detection.
Some experts suggest this may reflect better detection of smaller, earlier-stage tumours.
Despite rising incidence, mortality rates among young patients have remained relatively stable, suggesting the increase in cases may be largely due to increased diagnostic screening rather than a spike in lethal disease.
